Operation Period Research Articles

The concept of «force majeure» under the laws of Ukraine, the United Kingdom and the United States

The article analyzes the concept of force majeure provided for in Article 14-1 of the Law of Ukraine «On Chambers of Commerce and Industry in Ukraine» No. 671/97-ВР of December 2, 1997, which defines the list of circumstances falling under the concept of «force majeure». This list is quite broad, but not exhaustive. At the same time, such a list of force majeure circumstances did not exist before September 2, 2014, and this list appeared in connection with the anti-terrorist operation in eastern Ukraine after the entry into force of the Law of Ukraine «On Temporary Measures for the Period of Anti-Terrorist Operation» No. 1669-VII of September 2, 2014. It is emphasized that the Civil Code of Ukraine does not provide for the interpretation of such concepts as «force majeure» or «force majeure». The Commercial Code of Ukraine, in contrast to the Civil Code, states what are not extraordinary and unavoidable circumstances. Comparing the application of the concept of force majeure under Ukrainian law and UK law, it is worth noting that UK law does not provide for the concept of «force majeure» in legislation, as force majeure must be provided for in the contract. It is determined that the UK judiciary operates with the concept of «frustration», and the judiciary of the United States of America - with the concept of «commercial impracticability», which are inherently close to the doctrine of force majeure, although they contain some differences. Namely, the doctrine of force majeure refers to liability for non-performance or improper performance and is usually clearly defined in law, as is the doctrine of commercial impracticability in the United States of America. At the same time, the doctrine of «frustration» is not clearly provided for in English law. In addition, such doctrines also have different consequences: the doctrine of force majeure may be applied when it comes to exemption from liability for non-performance or improper performance of an obligation, while the doctrine of frustration and the doctrine of commercial impracticability are more likely to apply to the failure to perform an obligation in general, and even between these two doctrines there are certain differences, as noted by the court in The Aluminum Co. of America (ALCOA) v. Essex Group Inc. The doctrine of frustration may be applied when, if the parties had known about the change in circumstances and their impact on the relevant obligation, they would not have become a party to such an obligation. In turn, the doctrine of commercial impracticability relates more to the commercial component of the obligation and concerns unfavorable (in financial terms) consequences for one of the parties.

Study of Noise Reduction and Identification of Internal Damage Signals in Wire Ropes

Mining wire rope, a frequently used load-bearing element, suffers various forms of damage over extended periods of operation. Damage occurring within the wire rope, which is not visible to the naked eye and is difficult to detect accurately with current technology, is of particular concern. Consequently, the identification of internal damage assumes paramount importance in ensuring mine safety. This study proposes a wire rope internal damage noise reduction and identification method, first of all, through a three-dimensional magnetic dipole model to achieve the detection and analysis of the internal damage of the wire rope. Simultaneously, a sensor system capable of accurately detecting the internal damage of wire rope is developed and validated through experimentation. A novel approach is proposed to address the noise reduction issue in the design process. This approach utilizes a particle swarm optimization variational modal decomposition method to enhance the signal-to-noise ratio. Additionally, a dual-attention mode, which combines channel attention and spatial attention, is integrated into the CNN-GRU network model. This network model is specifically designed for the detection of internal damage in steel wire ropes. The proposed method successfully achieves quantitative identification of internal damage in steel wire ropes. The experimental findings demonstrate that this approach is capable of efficiently detecting internal damage in wire rope and possesses the capacity to quantitatively identify such damage, enabling adaptive identification of wire rope.

EXODONTIA DE DENTES IMPACTADOS – RELATO DE CASO

Dental impaction is characterized as a situation in which a tooth cannot completely emerge in its normal functional position, and may encounter another structure. Extracting an unerupted and impacted tooth is essential to avoid complications related to this type of pathology. Although tooth extraction surgeries are common in the professional’s daily life, the extraction of an element that has not reached its functional position can be complicated; especially if the dentist is not properly qualified or does not have mastery of the techniques necessary for this procedure. Cases of impaction of the lower second molar occur due to the reduction of space between the distal of the lower first molar and the anterior edge of the ascending ramus of the mandible and may or may not present painful symptoms. Exodontia is a predilection to be considered. Therefore, the purpose of this report is to report a clinical case of extraction of an impacted second molar and its justification is to emphasize the importance of the pre- operative period, which must adequately include anamnesis and complementary exams, and present transoperative techniques that were the difference for the case. Keywords: Impacted tooth. Exodontia. Surgical complications.

Decarbonization in Shipping—The Hopes and Doubts on the Way to Hydrogen Use

This article presents the initial processes of changing ship fuels aimed at reducing emissions of carbon dioxide and other greenhouse gases. A significant reduction in GHG emissions is only possible by using carbon-free fuels. The process of reducing CO2 emissions was forced by legal regulations introduced in recent years by the International Maritime Organization and the Parliament of the European Union. The year 2050 was set as the target year for achieving the intended goals, but intermediate goals should be achieved already in 2030 and 2040. This article attempts to analyze the ongoing changes in the fuel market in maritime transport on the way to achieving the threshold of climate neutrality with this form of transport. A number of hopes related to this were indicated but also so were obstacles that may slow down this process. In 2023, there was an increased interest among shipowners in adapting ship engines to burn more ecological ship fuels. However, it is far from our expectations. Meeting the gradually increasing emission limits through imposed regulations was possible in the years 2020–2023 by using dual-fuel engines in which gaseous fuels, mainly LNG and LPG, were used for long periods of operation. The next step is the use of biofuels or synthetic fuels, which, however, will not meet the requirements after 2030. Interest is moving towards the use of ammonia and, ultimately, after 2040, hydrogen. The aim of this article is to analyze the ongoing processes and assess the directions of changes that justify the sense of the actions taken.

Experimental and numerical investigation on the performance of binary solid-solid phase change materials with integrated heat pipe and aluminium foam based heat sink for thermal management of electronic systems

Phase change material (PCM) is widely utilised in thermal management systems (TMS), however its low thermal conductivity inhibits performance. Heat pipe and porous materials are incorporated into PCM due to their high thermal conductivities to form a hybrid system that substantially enhances PCM's heat transfer capability. This study investigates experimentally and numerically, the cooling performance of heat sink by integrating aluminium foam and heat pipe (HP) with binary Neopentyl glycol (NPG)/Trihydroxy methyl-aminomethane (TAM) solid-solid phase change material (SS_PCM) obtained at 90/10 wt% (N9T1), 70/30 wt% (N7T3) and 50/50 wt% (N5T5). Compared to pure NPG thermal conductivity, N9T1, N7T3, and N5T5 samples demonstrated relative enhancement ratios of 0.017, 2.46, and 2.84. Different heat sink configurations are examined at three constant power levels 15, 17 and 19 W for the same charging period of 10000 s to determine the optimal cooling arrangement. During the charging period, hybrid cooling (PCM-Foam-HP) system with fan in contrast to an empty sink achieved the highest temperature reduction of 58.31 %, 58.99 % and 59.89 % at power levels of 15, 17 and 19 W, respectively. N9T1, N7T3 and N5T5 combinations lowered temperature by 4.6 %, 5.9 % and 10.8 %, respectively, when compared to NPG. Furthermore, all configurations performed better at lower heat generation rates by extending the safe operational period (SOP).The investigation concluded that N5T5 SS_PCM-aided heat sinks with integrated aluminium foam and heat pipe with fan reduced temperatures the most and performed best in all aspects. Finally, the experimental results for TMS were numerically validated using COMSOL software.

Thermal Spray Nanostructured Coatings Integrated with Artificial Intelligence: A Sustainable Approach in Industry for Corrosion Applications

Coatings are the most common method for protecting metals from corrosion. The use of nano-sized coating materials can enhance the strength and decrease the porosity level of the developed coatings. The nano-coatings have shown improved mechanical properties, corrosion resistance, and wear resistance in recent studies. As a result, the use of nano-sized coatings can provide the benefit to the Industrial machinery components for longer operational periods. This review article covers the corrosion behavior of nano-structured coatings in the initial section followed by the role of artificial intelligence in predicting the corrosion rate of nanostructured coatings.

A novel sensor preference method for proton exchange membrane fuel cell flooding fault diagnosis based on multi-algorithm

ABSTRACT During periods of high-power operation, proton exchange membrane fuel cell (PEMFC) produce water, which gradually accumulates at the cathode. It causes flooding faults and significantly impacts on PEMFC safety. The data collected by the sensors is a fundamental prerequisite for the flooding faults diagnosis in PEMFC. Consequently, it is critical to select sensors. However, the conventional methods for selecting sensors consider sensitivity and noise immunity, the number of sensors selected and the flood diagnostic performance are not optimized. To solve the above problems, this paper proposes a sensor preference method that combines the Mantel test and Spearman coefficient (MS method). This method first uses the Mantel test to analyze the correlation between two flooding evaluation indicators and the sensors, it identifies suitable sensors for diagnosing flooding faults. Subsequently, the Spearman coefficient eliminates redundant sensors. Additionally, a one-dimensional convolutional neural network is employed to construct a flooding diagnosis model. The MS method is contrasted with two traditional sensor selection methods. The results show that the MS method selected sensors yield superior model training and enhanced accuracy in diagnosing flooding, thereby ensuring PEMFC safety.

Formation of a uniform velocity profile in the section of a profiled channel of a reference installation

The velocity profiles in gravity and pressure channels of flow diverters in reference installations in the field of liquid flow and quantity measurements are studied. The design shortcomings of reference installations that do not allow obtaining a flow velocity profile close to uniform in the sections of pressure nozzles over a long period of reference installation operation are described. It is shown that the placement of various straightening devices in the profiled channels and pressure nozzles of flow diverters of reference installations does not lead to obtaining a flow velocity profile close to uniform. An approach to profiling the gravity channel of the flow diverter is proposed, which allows obtaining a velocity profile close to uniform. An experimental justification of the hydraulic efficiency of the geometry of the flow part of the profiled channel of the flow diverter of the EU-3 reference installation from the State Primary Special Standard of Units of Mass and Volume of Liquid in a Flow, Mass and Volume Flow Rates of Liquid GET 63-2019 is presented. The influence of the flow velocity profile shape in the section of the profiled channel of the flow switch and the stability of the main hydro- and thermodynamic parameters of the water flow (flow rate, absolute pressure and temperature) in the pressure pipeline on the metrological characteristics of the reference installation is substantiated. Experimental studies of the velocity profile of the free-flow water flow in the section of the profiled channel are performed using high-speed total pressure meters and Pitot tubes. Close to uniform water flow velocity profiles in the section of a profiled channel were obtained for free flow in the range of investigated Reynolds numbers Re=(35...300)·103. The results of maintaining the stability of the specified value of the mass flow rate of water over a long period of time are presented. The equations for calculating the mass of water during transient processes are written down, taking into account the change in the thickness of the water flow and flow rate from zero to specified values. The presented approach and the obtained results are useful for manufacturers of reference installations and are relevant in the design, creation and modernization of profiled channels of flow switches of reference installations.

Evaluation of stresses on the surface of production columns equipped with sand filters when downing into a horizontal well

Relevance. The need to estimate the time of formation sand accumulation near the annulus of a horizontal well and the unit length of filter elements in the bottom of production strings and to determine the stresses on the surface of production strings equipped with sand filters when lowering into the well. Aim. Based on a study of the reasons for the continued flow of sand into wells equipped with anti-sand filters, to develop and propose measures related to the need to choose a reduction in the number of filters that provide the design flow rate of a horizontal well or a significant increase in the length of the filtering surface of the filters in order to reduce erosive wear of the wire winding. Objects. We are considering a well with a horizontal section, equipped with sand filters, the same size as the casing strings. It was assumed that the integrity of the surface of the filter elements would be preserved and the conditions for their destruction would be eliminated when lowering into the horizontal shaft. This presupposes the necessary efficient operation of the well throughout the entire operational period. The section of the first set of curvature and the forces arising during this are considered as wellas stability of a pipe string during possible stops. Centralizers are evenly located along the length of the column, then in some sections we will have a multi-span statically indeterminate beam, in each section of which a radial load acts. Methods. When studying the time of formation sand accumulation in the annular space of a horizontal well and a unit length of filter elements in the bottom of production strings, it is necessary at the first stage to determine the stresses on the surface of production strings equipped with sand filters when lowering into the well. Studying the assessment of the existence time of the transition period is of particular interest. This is, in other words, during what operational period there is a complete accumulation of formation sand in the annular space and the transition of formation drainage along the entire length of the horizontal wellbore to drainage of only zones adjacent to the filters. To calculate the fluid flow rate when the annular space of the horizontal well is completely filled with sand, the design values ​​of the AC4.8 formation parameters were used. The maximum value of depressions used in the calculations is assumed to be 1.5 MPa. Results. Consideration of situations that arise when filters are lowered into horizontal wells indicates that the outer surface of the filter elements is not protected from destruction as a result of contact stresses with the walls of the drilled wellbore. To protect against destruction and rubbing open gaps by clay-containing rocks, rigid centralizers should be installed along the edges of the filter elements, the maximum allowable distances between which should not exceed 4.0–4.5 m.

Repowering of a wind energy production field - case study of SIDI-DAOUD field in northeastern Tunisia

Every energy production system, whether conventional or renewable, reaches its final limits after a period of operation predefined by the feasibility study for such a project. Then we'll have to think about renewal to maintain a certain level of reliability and availability as a factor of operational safety. This project seeks of studying the repowering of two 1st phases of wind farm in Sidi-Daoued in north Tunisia, which have reached the end of their life (20 years); it aims to identify three new configurations and to simulate different scenarios to determine which types of turbines are the most optimal for a repowering project. The three types of wind turbine selected were Vestas 4200kw, Nordex Acciona and Siemens-Gamesa, each with a power output of 4500kw. These are the best-known types of wind turbine in the world, and the heights of the hubs are very similar, at around 105m, so that a comparison can be made between the three models. Therefore, the average speeds are around 7.8 m/s2.The final number of turbines to be installed on site is around 13 turbines for the three scenarios, but the result favours the second scenario with Siemens-GAMESA wind turbines, where the annual production can exceed 210.1 GWH with a capacity factor equal to 41 percent.

Impact of Extended Intervals on Diesel Engine Performance with 15W-40 DH1 Lubricant Oil

Engine lubricant oil is crucial for minimizing friction between moving components within an engine, directly influencing the engine's reliability and lifespan. Determining the appropriate oil replacement intervals is essential, as extending these intervals necessitates more rigorous monitoring of both oil quality and engine condition. This study investigated the performance of SAKAI 15W-40 DH1 engine oil in the SAKAI Vibrating Roller SV526 over varying operational periods: 125 hours, 250 hours, 375 hours, and 500 hours. The research involved analyzing oil samples for viscosity, metal additives, total base number (TBN), and contaminants using Fourier Transform Infrared Spectroscopy (FTIR). Additionally, key engine performance indicators, including fuel consumption, valve clearance, and compression pressure, were measured. The findings revealed a gradual decrease in oil viscosity from 13.48 cSt to 11.56 cSt, approaching the minimum acceptable threshold of 11.45 cSt. Concurrently, the Fe content in the oil increased to 11 ppm, indicating wear, while the valve clearance in cylinder number three expanded to 0.48 mm, and compression pressure dropped from 31 kg/cm² to 28 kg/cm². Despite these changes, the oil remained within the standard operational limits, and the engine continued to perform adequately. However, based on the observed trends, extending the oil replacement interval to 500 hours cannot be conclusively recommended, as the oil's condition and engine performance may begin to decline beyond this point.

Supraclavicular Brachial Plexus Block with and without Dexamethasone as Local Anaesthetics

Background: Brachial plexus block is good alternative to general anesthesia for upper limb surgery. This avoids the unwanted effect of anesthetic drugs used during general anesthesia and the stress of upper airway instrumentation. Peripheral nerve blocks can be used for anesthesia, postoperative analgesia, diagnosis and treatment of chronic pain disorders. This study was carried out to compare onset and duration of sensory and motor blockade and duration of postoperative analgesia on addition of dexamethasone to local anestheic and local anesthetic alone in supraclavicular brachial plexus block. Methods: In this prospective randomized, controlled, double blinded study which was conducted at Department of Anesthesia, 250 Beded Hospital, Lalmonirhat, Rangpur, Bangladesh from January to June 2023. We included 70 ASA I & II patients who were aged between 18 years & 60 years, underwent elective upper limb surgeries. They were divided into two equal groups. Group 1 (cases) who received 15 milliliter of 2% lignocaine with adrenaline and 15 milliliter of 0.5% bupivacaine + dexamethasone 8mg (2ml). Group 2 (controls) who received 15 milliliter of 2% lignocaine with adrenaline and 15 milliliter of 0.5% bupivacaine + 0.9% normal saline (2ml). We observed the Onset of sensory and motor blockade, duration of sensory and motor blockade and postoperative analgesia between the two groups. Results: In this study of patients according to their age and weight. 37.26±15.55 years were mean age in group 1 and in group 2 it was 36.56±16.86 with p value being 0.8678. 58.466± 3.9642 kg was the mean weight in group 1 and in group 2 it was 60.4±4.95 kg with p value of 0.1002. So both the groups were comparable in terms of age and weight. In this study out of 70 patients, group1 consisted of 68.6% males whereas there were 60% in group 2 and group 1consisted of 31.4% of females and 40% in group2, hence males’ outnumbered females in both the groups. The mean duration of surgery in group 1 was 50±19.95 minutes and in group 2 were 46.6±15.55 minutes with p value of 0.4646. There was no statistical difference between both the groups. The onset of sensory blockade was within 7.3 min in group 1. In group 2 the onset of sensory blockade was 13.66 minutes. The onset of motor blockade was within 3.93 min in group 1. In group 2 the onset of motor blockade was 18.66 min. The duration of intra operative analgesia was 654.33 minutes in group 1. In group 2 the duration of intra operative analgesia was 292.6 minutes. The duration of post-operative analgesia was 815±13.57 minutes in group 1. The duration of post-operative analgesia in group 2 was 393.8±42.88 minutes. There were no complications in both the groups in intra operative period and post-operative period. Conclusion: Dexamethasone, when added to 15 millilitre of 0.5% bupivacaine and 15 millilitre of 2% lignocaine plus adrenaline, very effectively enhances the onset of sensory and motor blockade. It dramatically prolongs the duration of sensory and motor blockade and duration of analgesia. There were no untoward side effects with the use of dexamethasone as an additive in the brachial plexus block.

Drug delivery from a ring implant attached to intraocular lens: An in-silico investigation

Multiple iterations required to design ocular implants, which will last for the desired operational period of months or even years, necessitate the use of in-silico models for ocular drug delivery. In this study, we developed an in-silico model to simulate the flow of Aqueous Humor (AH) and drug delivery from an implant to the Trabecular Meshwork (TM). The implant, attached to the side of the intraocular lens (IOL), and the TM are treated as porous media, with their effects on AH flow accounted for using the Darcy equation. This model accurately predicts the physiological values of Intraocular Pressure (IOP) for both healthy individuals and glaucoma patients, as reported in the literature. Results reveal that the effective diffusivity of the drug within the implant is the critical parameter that can alter the bioavailability time period (BTP) from a few days to months. Intuitively, BTP should increase as effective diffusivity decreases. However, we discovered that with lower levels of initial drug loading, BTP declines when effective diffusivity falls below a specific threshold. Our findings further reveal that, while AH flow has a minimal effect on the drug release profile at the implant site, it significantly impacts drug availability at the TM.

Towards Resource Durability of Bridge Spans

The paper studies durability of metal bridge spans as resource reliability and operability characterized by their performance specifications and maintainability before the limiting state. The ultimate condition of superstructures, in which further operation is impractical without restoration work to ensure operation conditions. The qualitative assessment of the resource durability of superstructures is based on the supposition that they maintain the normative operability at least for the specified operational period from incubation and service life to residual resource, indicating the possibility of removing the superstructure beyond the "serviceable" limit.

Buprenorphine: Not Just Another Opioid - Understanding the World's Most Interesting Opioid.

In this talk we will delve deep into the pharmacology of this drug and how it's receptor interactions are unique and then we will take that understanding and apply it to clinical usage to see how this drug behaves in a variety of situations. Specifically we will look at the safety profile of this drug, including it's ceiling effect on respiratory depression. Then we will look at efficacy, how well does this drug work in the treatment of pain. We will look at analgesia, tolerance and anti-hyperalgesic properties of buprenorphine. We will discus why this drug is so versatile anyhow versatility is a key asset when it comes to using buprenorphine for the treatment of pain. The last section of this talk will look at the specific area of preoperative use of buprenorphine and why buprenorphine should be continued throughout the pre- operative period.

Designing for Degradation: Transient Devices Enabled by (Nano)Cellulose.

Transient technology involves materials and devices that undergo controlled degradation after a reliable operation period. This groundbreaking strategy offers significant advantages over conventional devices based on non-renewable materials by limiting environmental exposure to potentially hazardous components after disposal, and by increasing material circularity. As the most abundant naturally occurring polymer on Earth, cellulose is an attractive material for this purpose. Besides, (nano)celluloses are inherently biodegradable and have competitive mechanical, optical, thermal, and ionic conductivity properties that can be exploited to develop sustainable devices and avoid the end-of-life issues associated with conventional systems. Despite its potential, few efforts have been made to review current advances in cellulose-based transient technology. Therefore, this review catalogs the state-of-the-art developments in transient devices enabled by cellulosic materials. To provide a wide perspective, the various degradation mechanisms involved in cellulosic transient devices are introduced. The advanced capabilities of transient cellulosic systems in sensing, photonics, energy storage, electronics, and biomedicine are also highlighted. Current bottlenecks toward successful implementation are discussed, with material circularity and environmental impact metrics at the center. It is believed that this review will serve as a valuable resource for the proliferation of cellulose-based transient technology and its implementation into fully integrated, circular, and environmentally sustainable devices.

Functional performance of patients submitted to cardiac surgery with different levels of sleep quality: an observational study

ObjectiveTo describe pulmonary function, muscle strength and functional performance in the different qualities of sleep and the impact of this on the number of physiotherapeutic assistances. MethodsThis is an observational study. In the pre and post operative period, sleep behavior was evaluated using the Pittsburgh questionnaire. Patients were divided into three groups: Good Sleep Quality (GSQ), Poor Sleep Quality (PSQ) and Sleep Disordered (SDB). At this time, other tests were also performed, such as: 6-Minute Walk Test (6MWT), Sit and Stand Test (SST), gait speed test and Timed Up to Go (TUG), Medical Research Council (MRC), maximal inspiratory pressure and maximal expiratory, vital capacity and peak expiratory flow. The functional performance and lung function of each group were compared. ResultsA total of 105 people, undergoing cardiac surgery and admitted to hospital were evaluated, 33 with GSQ, 41 with PSQ and 31 with SD. Patients who were in the SDB group had a lower functional performance than the other groups. 6MWT (meters) in the GSQ was 499 ± 87, versus 487 ± 91 in the PSQ and 430 ± 78 in the SD (p = 0.02). In the SST (seconds) it was 10.4 ± 1.1 in the GQS, 11.1 ± 2.3 in the PSQ and 15.4 ± 2.1 in the SD (p = 0.04). Lung function and muscle strength did not differ between groups. Regarding the refusal to perform physical therapy, the SD group was more incident, the main reason being drowsiness. ConclusionBased on the results, we found that sleep quality interferes with functional performance and physical therapy assistance during the hospital stay in patients undergoing cardiac surgery.

Laser Hemorrhoidoplasty and Lateral sphincterotomy Procedures vs Conservative Treatment for Hemorrhoids and Fissure in Ano: A Trial Comparing Laser and Conservative treatments

Objective: According to the ‘‘vascular’’ theory, arterial overflow in the superior hemorrhoidal arteries would lead to dilatation of the hemorrhoidal venous plexus. Hemorrhoid laser procedure (LHP) is a new laser procedure for outpatient treatment of hemorrhoids in which hemorrhoidal arterial flow feeding the hemorrhoidal plexus is stopped by laser coagulation. Aim: Our aim was to compare the hemorrhoid laser procedure and laser aided lateral sphincterotomy vs conservative treatment of symptomatic hemorrhoids and fissure in ano. Material and Method: A comparison trial between hemorrhoid laser procedure, lateral sphincterotomy and conservative treatment for hemorrhoids and fissure in ano was made. This study was conducted at Vels Medical College and Hospital, Manjankaranai, Tamil Nadu. Patients with symptomatic grade III or grade IV hemorrhoids with minimal or complete mucosal prolapse were eligible for the study: 30 patients treated with the laser hemorrhoidoplasty, 30 patients–with laser aided lateral sphincterotomy and 40 patients treated with conservative methods. Operative time, postoperative pain, post-op healing time were evaluated. Results: A total number of 100 patients ( 65 men and 35 women, mean age, 46 years) entered the trial. Significant differences between laser hemorrhoidoplasty, laser sphincterotomy and conservative treatments were observed in operative time and early postoperative pain. The procedure time for LHP was 15.49 min laser aided lateral sphincterotomy was 10.19 min. Conclusion: The laser hemorrhoidoplasty and laser guided sphincterotomy procedures were more effective than conservative methods. Postoperative pain and healing time were drastically less in the early and late post op period.

The concept of microfiltration of hydraulic oil in rail vehicles

The article presents the issue of microfiltration of hydraulic oil from metallic impurities and water that deteriorate the properties of the oil. Tests carried out on oils have shown that periodic oil replacement in machines or vehicles in accordance with their maintenance documentation ensures that the system is emptied of 95% of impurities from the old oil before pouring the new one. The remaining part, i.e. 5% of impurities, together with the oil remaining on the walls of the pipes or inside other hydraulic devices, will mix with the new oil, reducing its cleanliness class. Periodic replacement of hydraulic oil will not allow for complete cleaning of the system. In extreme cases, poor oil condition may cause disruptions in the operation of the machine with the hydraulic system or its downtime for oil replacement or repair. Filtering the oil in the system while the machine is running will clean the oil from impurities and water, extend the oil's service life, without disabling the hydraulic system. The article includes, among others: The justification for the use of microfiltration of hydraulic oil with portable filtering devices in order to extend the service life of the oil until the next replacement is presented. The main purpose of the article is to present the methodology for testing hydraulic oil in accordance with the requirements of ISO, NAS and SAE in order to assign the oil to a given cleanliness class. Additionally, the results of testing the oil cleanliness class in various periods of operation of the machine with the hydraulic installation on a portable measuring device were presented.

A Study of Carbon Emissions during the Operational Period of an Integrated Expressway Construction Station

An integrated construction station for an expressway is characterized by complex carbon emission sources and high carbon emission intensity. Conducting carbon emissions accounting makes possible a comprehensive understanding of these characteristics, enabling targeted and guided carbon reduction efforts, which is crucial for advancing the low-carbon development of expressway construction. This paper, based on an in-depth analysis of the carbon emission structure during the operational period of an integrated expressway construction station identifies, as calculation boundaries, eight categories: residential areas, station transportation, mixing stations, precast beams, steel bar yards, artificial carbon emissions, chemical reactions during construction, and construction conditions. The study adopts a “bottom-up” approach to carbon emission measurement and constructs a carbon emission model for the production and operational period of the integrated construction station, based on the carbon emission factor method. Using the SG-2 section of the Fengqiu to Xiuwu stretch of the Changxiu Expressway as an engineering case, carbon emissions accounting for each component of the integrated construction station’s operational period was conducted, and the results were compared with the station’s monitoring system. High-precision characterization and calculation of total carbon emissions, as well as emissions from each process and piece of equipment during the operational period, were achieved. The results indicate that: (1) the relative error between the overall calculation results and actual monitoring is 3.6%, verifying the model’s accuracy; (2) the monthly carbon emissions of the integrated construction station during the operational period reached 72.15 tons; (3) there is a significant difference in carbon emissions among the different processes, with the highest emissions coming from transportation and residential areas, accounting for 43.4% and 23.7%, respectively. Therefore, electrification of transportation equipment could significantly reduce the overall carbon emissions of the integrated construction station.